The Jack Higgins novel "The Eagle Has Landed" is well known from the film of the same name.
It is 1943 and a group of crack German paratroopers land in Norfolk, disguised as British soldiers. There aim - to kidnap Winston Churchill. The plot owes more than a little to Graham Greene's 1942 film script "Went The Day Well?" but is enjoyable enough for all that.
Also included is the less satisfactory sequel "The Eagle Has Flown", in which Liam Devlin must attempt to rescue Kurt Steiner from under the noses of the British and not fall into the trap laid for him.